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BACKGROUND: Phycocyanin (PC), a natural blue photosynthetic pigment found in cyanobacteria, rhodophyta and cryptophyta has numerous applications in biotechnology and the food industry. The phycocyanin extraction method has a significant impact on its bioactivities, purity index, cost and potential applications; thus, the development of an efficient extraction strategy continues to be a primary research goal. RESULTS: This study evaluated the efficacy of different methods for the extraction of cyanobacterial phycocyanin (C‐PC) from three marine cyanobacterial isolates, namely Arthrospira platensis, Phormidium sp. and Pseudoscillatoria sp. wet biomass. The pretreatment step of soaking biomass in extraction buffer for 60 min, followed by a combination of freeze–thaw (one cycle; 2 h) and sonication (2 min) treatment was found to be the most effective extraction strategy, producing the highest C‐PC yield (16.19 ± 0.34%, 15.89 ± 0.61% and 15.56 ± 0.69% dry cell weight for strains A. platensis, Phormidium sp. and Pseudoscillatoria sp., respectively). Furthermore, a biomass‐to‐solvent ratio of 0.02 g mL−1 was optimal to attain food‐grade purity ((A620/A280) ≥ 0.7). Bioactivity evaluation of crude and purified C‐PC exhibited its potential as antioxidant compounds and as an antimicrobial agent with significant inhibitory effects against various pathogenic microorganisms. CONCLUSION: The study proposed an efficient and cost‐effective C‐PC extraction process for cyanobacteria and highlighted the potential of C‐PC as a valuable bioactive compound with various applications. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Carotenoids are hydrophobic pigments produced exclusively by plants, fungi, and specific microbes. Microalgae are well suited for the production of valuable carotenoids due to their rapid growth, efficient isoprenoid production pathway, and ability to store these compounds within their cells. The possible markets for bio-products range from feed additives in aquaculture and agriculture to pharmaceutical uses. The production of carotenoids in microalgae is affected by several environmental conditions, which can be utilized to enhance productivity. The current study focused on optimizing the extraction parameters (time, temperature, and extraction number) to maximize the yield of carotenoids. Additionally, the impact of various nitrogen sources (ammonia, nitrate, nitrite, and urea) on the production of lutein and loroxanthin in Scenedesmus obliquus was examined. To isolate the carotenoids, 0.20 g of biomass was added to 0.20 g of CaCO3 and 10.0 mL of ethanol solution containing 0.01% (w/v) pyrogallol. Subsequently, the extraction was performed using an ultrasonic bath for a duration of 10 min at a temperature of 30 °C. This was followed by a four-hour saponification process using a 10% methanolic KOH solution. The concentration of lutein and loroxanthin was measured using HPLC–DAD at 446 nm, with a flow rate of 1.0 mL/min using a Waters YMC C30 Carotenoid column (4.6 × 250 mm, 5 μm). The confirmation of carotenoids after their isolation using preparative chromatography was achieved using liquid chromatography–tandem mass spectrometry (LC–MS/MS) with an atmospheric pressure chemical ionization (APCI) probe and UV–vis spectroscopy. In summary, S. obliquus shows significant promise for the large-scale extraction of lutein and loroxanthin. The findings of this study provide strong support for the application of this technology to other species. [ABSTRACT FROM AUTHOR]

Microalgae produce a variety of high-value chemicals including carotenoids. Fucoxanthin is also a carotenoid that has many physiological functions and biological properties. For this reason, the cost-effective production of fucoxanthin at an industrial scale has gained significant attention. In the proposed study, fucoxanthin production was aimed to be increased by altering the culture conditions of N. shiloi. The effect of light intensity aeration rate, different nitrogen sources, and oxidative stress on the biomass and fucoxanthin productivity have been discussed. Based on these results, the fucoxanthin increased to 97.45 ± 2.64 mg/g by adjusting the light intensity to 50 µmol/m2s, and aeration rate at 5 L/min using oxidative stress through the addition of 0.1 mM H2O2 and 0.1 mM NaOCl to the culture medium. Fucoxanthin was then purified with preparative HPLC using C30 carotenoid column (10 mm × 250 mm, 5 μm). After the purification procedure, Liquid chromatography tandem mass spectrometry (LC–MS/MS) and UV-vis spectroscopy were employed for the confirmation of fucoxanthin. This study presented a protocol for obtaining and purifying considerable amounts of biomass and fucoxanthin from diatom by manipulating culture conditions. With the developed methodology, N. shiloi could be evaluated as a promising source of fucoxanthin at the industrial scale for food, feed, cosmetic, and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

Maintenance of eukaryotic microalgae strains for the long term is generally carried out using serial subculture techniques which require labour, time and cost. Cryopreservation techniques provide long-term storage of up to years for numerous microorganism strains and cell cultures. Ssu930ijn vbvbhnn8;l,n is related to a successfully designed mass and heat transfer balance throughout the cell. In this study, optimization of the cryopreservation process was carried out for two commercially used microalgal strains. The parameters to be optimized were DMSO percentage (0–25%), incubation time (1–15 min) and cryopreservation term (7–180 days) using a central composite design (CCD). Long-term storage up to 123.17 and 111.44 days corresponding to high cell viabilities was achieved for Chlorella vulgaris and Neochloris texensis, respectively. Generated models were found to be in good agreement with experimental results. The study also revealed holistic results for storage of microalgal strains in a stable state for industrial applications. [ABSTRACT FROM AUTHOR]

Microalgae with their improved growth rates and accumulation of high-value-added products make their commercial production attractive. Among them, lutein, which is a carotenoid, plays a very important role due to its various applications in the food and pharmaceutical industry. Induction of its biosynthesis can be triggered by various stress conditions like light. In this study, three different light intensities (50,150 and 300 µmol photons/m²s) and aeration rates (1, 3, and 5 L/min) were utilized to induce the lutein biosynthesis and biomass productivity in Scenedesmus obliquus. Lutein was isolated by preparative chromatography using a semiprep C30 column (10 × 250 mm, 5µm) and its confirmation was made by LC-MS/MS. According to the results, Scenedesmus obliquus synthesized the maximum lutein (8.01 ± 0.1 mg/g) with biomass productivity of 1.698 g/L at 150 µmol photons/m²s light intensity using 3 L/min as aeration rate. To the best of the authors' knowledge, this was the first study that the lutein was isolated by preparative chromatography using semiprep C30 carotenoid column with a simple and rapid separation, which can be used as a reference methodology for the isolation of other carotenoids. Scenedesmus obliquus can be an important alternative source for commercial production of lutein, as it is indicated from the results of this study. [ABSTRACT FROM AUTHOR]

Spray‐drying method was used for the microencapsulation of the extracted, purified phycocyanin from Arthrospira platensis to increase its stability and usability as a food colorant. The effect of process conditions – wall material type, ratio, and inlet‐air temperature – on physical and chemical properties was investigated. The moisture content and water activity of phycocyanin microcapsules were found as 1.80–3.18% and 0.15–0.24, respectively. The product with the largest particle size was 19.44 μm. Size distribution values were in 1.87–6.05. Optimum process condition was determined as 34.4% maltodextrin, 65.6% whey protein isolate, and 167.6°C inlet temperature. Moisture content (2.35%), aw (0.18), Tg (58.25°C), D[4,3] (11.92 μm), size distribution (2.016), color properties (L*: 79.37, a*: −6.69, b*: −5.29), total phenolic content (12.14 mgGA/L), and microencapsulation efficiency (87.11%) of the phycocyanin microcapsules were also determined at optimum. Microencapsulation efficiency increased with the maltodextrin and whey protein isolate together; the conditions of process variables were effective in the encapsulation process. Novelty impact statement: Phycocyanin was prepared in a double‐layer emulsion and dried in a spray dryer, thus preventing degradation caused by environmental factors.The physical and chemical properties of the final product were examined and modeled.The conditions required to obtain the microencapsulated phycocyanin with optimum properties were examined. [ABSTRACT FROM AUTHOR]

Herein we investigated the utilization of various encapsulation materials of blue pigments phycocyanin from Arthrospira platensis extract by spray drying to ensure the stability in foods. Various combinations and ratios of wall materials (maltodextrin, gum arabic, whey protein isolate, and sodium caseinate) were tried to examine the emulsion characterization, physical properties, and efficiency of the microcapsules. The moisture content and water activity of the microcapsules having different wall materials were quite similar to each other. However, wall material type and ratio significantly affected the solubility, color values, and microencapsulation efficiency. While the highest microencapsulation efficiency (91.19% ± 0.88%) was achieved with a combination of gum arabic and whey protein isolate as wall material, the highest blueness index was observed in phycocyanin powder encapsulated with maltodextrin and whey protein isolate. Novelty impact statement: Microencapsulation by spray drying method was preferred for protecting phycocyanin from external factors that improve its stability. The effect of typical wall materials based on carbohydrate (maltodextrin, gum arabic) and protein based (whey protein isolate, sodium caseinate) on the feed emulsion and the properties of the final powder product was investigated in detail. In the development of microcapsules, the highest microencapsulation efficiency was obtained in gum arabic and cheese protein isolate, but combinations of maltodextrin and whey protein isolate wall material, attractive blue color, and acceptable microencapsulation efficiency were achieved. [ABSTRACT FROM AUTHOR]

BACKGROUND The aim of this study was to investigate how the synergistic protocols between nutrient and light affect the cell growth, lipid content and fatty acid profile of Cylindrotheca closterium. Furthermore, the flow hydrodynamics of a laboratory scale internal loop air-lift photobioreactor were investigated for the cultivation of C. closterium. RESULTS Maximum lipid productivity of 7.364 mg L−1 d−1, which corresponded to the maximum biomass production of 0.356 g L−1, was obtained in F/2 medium under light intensity of 56 μE m−2 s−1, highlighting the importance of high biomass accumulation for efficient lipid production. The most abundant saturated and monounsaturated fatty acids were pentadecanoic acid ( C15:0) and palmitoleic acid ( C16:1) which constituted 16-45% and 17-35% of total fatty acids for all growth conditions, respectively. CONCLUSION Palmitoleic acid was the dominant monounsaturated fatty acid, followed by oleic acid, whereas the most abundant saturated fatty acids were pentadecanoic acid and palmitic acid for C. closterium. Another notable outcome was that the fatty acid content increased in N-free medium under low light intensity, while nitrogen starvation did not affect the fatty acid content under high light intensity. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the optimal physical process conditions for the cultivation of locally isolated strains of Nannochloropsis sp. and Tetraselmis striata to achieve maximum growth rate. It was essential to evaluate biomass production at different agitation rates, light intensities, and temperature levels. Central composite design and response surface methodology were applied to design the experiments and optimize the cultivation process for Nannochloropsis sp. and T. striata. The specific growth rate of 0.250 d−1 was obtained for Nannochloropsis sp. cells under the light intensity of 54 μmol photons · m−2 · s−1, at the agitation rate of 151 rpm in 24.5°C. The optimal physical process conditions for T. striata were obtained under the light intensity of 56 μmol photons · m−2 · s−1 in 25.5°C at the agitation rate of 151 rpm in 25.5°C, resulting in a specific growth rate of 0.226 d−1. The predicted values were justified by the verification tests. Good agreement between the predicted values and the experimental values confirmed the validity of the models for the cultivation of microalgal strains. In this article, the noteworthy result was that temperature was a dominant factor in obtaining high chl- a content for Nannochloropsis sp., whereas the growth of T. striata strongly depended on light exposure. [ABSTRACT FROM AUTHOR]

Ettlia oleoabundance (formerly known as Neochloris oleoabundance) is an attractive candidate for biodiesel production because of its high lipid accumulation, and it's taking the majority of the attention among the strains of Ettlia genus; however, potential of the other genus members is unknown. An indigenous strain from Salda Lake (South West Turkey) identified by 18S rDNA sequencing as Ettlia texensis (GenBank accession no: JQ038221), and its fatty acid and carotenoid compositions under phototrophic and mixotrophic conditions was investigated to evaluate the potential of the strain for commercial uses. A threefold increase was observed in total lipid content (total fatty acids; from 13 % to 37 %) in mixotrophic culture respect to the phototrophic growth conditions. The oleic acid (C18:1) and alpha-linolenic acid (18:3) were the major unsaturated fatty acids accounting for 40 % and 13.2 % of total fatty acids in mixotrophic culture, respectively. Carotenoid analyses of the mixotrophic culture revealed the metabolite canthaxanthin, a commercially valuable carotenoid used mainly for food coloring, was the major constituent among other pigments. The possible use of E. texensis in biotechnological applications is discussed. [ABSTRACT FROM AUTHOR]

The prevalence of allergic rhinitis is increasing globally due to various causes. It affects the quality life of a large group of people in all around the world. Allergic rhinitis still remains inadequately controlled with present medical means. The need of continuous medical therapy makes individuals anxious about the side effects of the drugs. So there is a need for an alternative strategy. Effects of spirulina, tinospora cordifolia and butterbur were investigated recently on allergic rhinitis in just very few investigations. Spirulina represents a blue-green alga that is produced and commercialized as a dietary supplement for modulating immune functions, as well as ameliorating a variety of diseases. This double blind, placebo controlled study, evaluated the effectiveness and tolerability of spirulina for treating patients with allergic rhinitis. Spirulina consumption significantly improved the symptoms and physical findings compared with placebo ( P < 0.001***) including nasal discharge, sneezing, nasal congestion and itching. Spirulina is clinically effective on allergic rhinitis when compared with placebo. Further studies should be performed in order to clarify the mechanism of this effect. [ABSTRACT FROM AUTHOR]